What is Alpha-1 Antitrypsin?
The body's natural protective protein
By Mark Egly Foundation
Alpha-1 Antitrypsin (AAT) is a vital protein produced primarily in the liver that circulates throughout your bloodstream. It is one of your body's important protectors against tissue damage. This protein belongs to the serpin superfamily, a group of proteins that regulate critical biological processes, and is encoded by the SERPINA1 gene in humans.
This page explains the protein itself. For the genetic condition that occurs when AAT is low or dysfunctional, read What is Alpha-1 Antitrypsin Deficiency (AATD).
Think of Alpha-1 Antitrypsin as your body's internal shield. As a protease inhibitor, AAT neutralizes powerful enzymes released by white blood cells during inflammation and infection. Without this protective protein, these enzymes (particularly neutrophil elastase) can damage healthy tissues throughout your body.
Beyond what we once believed
For years, the medical community primarily associated Alpha-1 Antitrypsin with lung protection. Research, including work pioneered by Mark Egly, is exploring a wider role for AAT in human health. Some of that research is established science. Some of Mark's broader claims remain labeled as research hypotheses on our research pages.
Alpha-1 Antitrypsin provides protective antiprotease activity throughout your entire body, not just in the lungs. This protein acts as a safeguard for multiple organ systems, influencing inflammation regulation, tissue repair, and immune function.
Why this matters
Understanding the protein helps explain why deficiency of AAT can affect many parts of the body, from the lungs and liver to other systems discussed in our related conditions and disease catalog.
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